NEET Electromagnetic Induction — Set 6

Question 1

A circular loop is placed in a uniform magnetic field, and the field strength is increased steadily. What determines the magnitude of the induced emf in the loop?

Accepted Answer

According to Faraday’s law, the induced emf depends on the rate of change of magnetic flux, which increases with the rate at which the magnetic field strength changes.

Question 2

A conducting loop is expanded in a uniform magnetic field. The induced emf is caused by what physical process?

Accepted Answer

Expanding the loop increases the magnetic flux through it, and the rate of this flux change induces an emf as per Faraday’s law.

Question 3

A rectangular loop of sides 10 cm and 5 cm moves out of a 0.2 T magnetic field at 2 m/s perpendicular to the longer side. What is the motional emf induced?

Accepted Answer

For motional emf: $ \varepsilon = B l v $, where $ l $ is the length perpendicular to velocity. Here, $ B = 0.2 \, \text{T} $, $ l = 0.05 \, \text{m} $, $ v = 2 \, \text{m/s} $. $ \varepsilon = 0.2 \times 0.05 \times 2 = 0.02 \, \text{V} $.

NEET Physics: Electromagnetic Induction — Practice Set 6

Q1. A circular loop is placed in a uniform magnetic field, and the field strength is increased steadily. What determines the magnitude of the induced emf in the loop?

Q2. A conducting loop is expanded in a uniform magnetic field. The induced emf is caused by what physical process?

Q3. A rectangular loop of sides 10 cm and 5 cm moves out of a 0.2 T magnetic field at 2 m/s perpendicular to the longer side. What is the motional emf induced?

Q4. A coil with \( L = 0.15 \, \text{H} \) has its current increased from 0 to 3 A in 0.3 s. What is the energy stored?

Q5. A solenoid with mutual inductance 0.35 H has a current change of 4 A/s in the primary coil. What is the induced emf in the secondary coil?

Q6. A solenoid of 850 turns per meter and area 0.017 m² has a current drop from 10 A to 7 A in 0.25 s. What is the self-induced emf? (\( \mu_0 = 4\pi \times 10^{-7} \, \text{H/m} \))

Q7. In a setup with two coils, if the primary coil’s current is constant DC, what will be the induced emf in the secondary coil?

Q8. A coil of self-inductance 0.9 H has its current increased from 1 A to 4 A in 0.25 s. What is the magnitude of the induced emf?

Q9. A circular coil of radius 6 cm and 200 turns rotates at 30 rad/s in a 0.08 T field. What is the maximum emf induced?

Q10. A coil of self-inductance 0.7 H has its current increased from 2 A to 5 A in 0.3 s. What is the magnitude of the induced emf?